Referring to FIG. 1, a conventional rotatable armrest 1 contains a fixing mount 11 locked on one side of a chair 10, a toothed disc 12 connected with the fixing mount 11, a movable seat 13 coupled with an armrest 17, a resilient element 14 defined between the toothed disc 12 and the movable seat 13, and a screw bolt 15 inserted through a rotating knob 16 so as to screw with the movable seat 13 and the fixing mount 11, such that the movable seat 13 cooperates with the toothed disc 12 so as to position the rotatable armrest 1.
As desiring to rotate the armrest 17, the rotating knob 16 is rotated loosely so that the resilient element 14 pushes the toothed disc 12, and then the armrest 17 is rotated backwardly to be close to a chair back, thereafter the rotating knob 16 is rotated tightly so that the screw bolt 15 forces the movable seat 13 and the fixing mount 11 to engage with the toothed disc 12, thereby rotating and positioning the armrest 17.
However, before rotating the armrest 17, the rotating knob 16 is rotated several circles so that the toothed disc 12 disengages from the movable seat 13, and after the armrest 17 is rotated, the rotating knob 16 is rotated several circles again so as to fix the armrest 17, thus having troublesome operation. In addition, the rotatable armrest 1 is complicated to cause high production cost.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.